3
3
* Mandos plugin runner - Run Mandos plugins
5
* Copyright © 2008,2009 Teddy Hogeborn
6
* Copyright © 2008,2009 Björn Påhlsson
8
* This program is free software: you can redistribute it and/or
9
* modify it under the terms of the GNU General Public License as
10
* published by the Free Software Foundation, either version 3 of the
11
* License, or (at your option) any later version.
13
* This program is distributed in the hope that it will be useful, but
5
* Copyright © 2008-2018 Teddy Hogeborn
6
* Copyright © 2008-2018 Björn Påhlsson
8
* This file is part of Mandos.
10
* Mandos is free software: you can redistribute it and/or modify it
11
* under the terms of the GNU General Public License as published by
12
* the Free Software Foundation, either version 3 of the License, or
13
* (at your option) any later version.
15
* Mandos is distributed in the hope that it will be useful, but
14
16
* WITHOUT ANY WARRANTY; without even the implied warranty of
15
17
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16
18
* General Public License for more details.
18
20
* You should have received a copy of the GNU General Public License
19
* along with this program. If not, see
20
* <http://www.gnu.org/licenses/>.
21
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
22
* Contact the authors at <mandos@fukt.bsnet.se>.
23
* Contact the authors at <mandos@recompile.se>.
25
26
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
asprintf(), O_CLOEXEC */
27
28
#include <stddef.h> /* size_t, NULL */
28
29
#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
30
31
#include <stdbool.h> /* bool, true, false */
31
32
#include <stdio.h> /* fileno(), fprintf(),
32
stderr, STDOUT_FILENO */
33
#include <sys/types.h> /* DIR, fdopendir(), stat(), struct
34
stat, waitpid(), WIFEXITED(),
35
WEXITSTATUS(), wait(), pid_t,
36
uid_t, gid_t, getuid(), getgid(),
33
stderr, STDOUT_FILENO, fclose() */
34
#include <sys/types.h> /* fstat(), struct stat, waitpid(),
35
WIFEXITED(), WEXITSTATUS(), wait(),
36
pid_t, uid_t, gid_t, getuid(),
38
38
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
39
39
FD_SET(), FD_ISSET(), FD_CLR */
40
40
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
41
WEXITSTATUS(), WTERMSIG(),
43
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
41
WEXITSTATUS(), WTERMSIG() */
42
#include <sys/stat.h> /* struct stat, fstat(), S_ISREG() */
44
43
#include <iso646.h> /* and, or, not */
45
#include <dirent.h> /* DIR, struct dirent, fdopendir(),
46
readdir(), closedir(), dirfd() */
47
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
48
fcntl(), setuid(), setgid(),
49
F_GETFD, F_SETFD, FD_CLOEXEC,
50
access(), pipe(), fork(), close()
51
dup2(), STDOUT_FILENO, _exit(),
52
execv(), write(), read(),
44
#include <dirent.h> /* struct dirent, scandirat() */
45
#include <unistd.h> /* fcntl(), F_GETFD, F_SETFD,
46
FD_CLOEXEC, write(), STDOUT_FILENO,
47
struct stat, fstat(), close(),
48
setgid(), setuid(), S_ISREG(),
49
faccessat() pipe2(), fork(),
50
_exit(), dup2(), fexecve(), read()
54
52
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
56
#include <string.h> /* strsep, strlen(), asprintf(),
57
strsignal(), strcmp(), strncmp() */
53
FD_CLOEXEC, openat(), scandirat(),
55
#include <string.h> /* strsep, strlen(), strsignal(),
56
strcmp(), strncmp() */
58
57
#include <errno.h> /* errno */
59
58
#include <argp.h> /* struct argp_option, struct
60
59
argp_state, struct argp,
488
513
plugin *p = getplugin(arg);
490
515
p->disabled = false;
494
520
case 128: /* --plugin-dir */
496
522
plugindir = strdup(arg);
523
if(plugindir != NULL){
498
527
case 129: /* --config-file */
499
528
/* This is already done by parse_opt_config_file() */
501
530
case 130: /* --userid */
502
tmpmax = strtoimax(arg, &tmp, 10);
531
tmp_id = strtoimax(arg, &tmp, 10);
503
532
if(errno != 0 or tmp == arg or *tmp != '\0'
504
or tmpmax != (uid_t)tmpmax){
533
or tmp_id != (uid_t)tmp_id){
505
534
argp_error(state, "Bad user ID number: \"%s\", using %"
506
535
PRIdMAX, arg, (intmax_t)uid);
511
541
case 131: /* --groupid */
512
tmpmax = strtoimax(arg, &tmp, 10);
542
tmp_id = strtoimax(arg, &tmp, 10);
513
543
if(errno != 0 or tmp == arg or *tmp != '\0'
514
or tmpmax != (gid_t)tmpmax){
544
or tmp_id != (gid_t)tmp_id){
515
545
argp_error(state, "Bad group ID number: \"%s\", using %"
516
546
PRIdMAX, arg, (intmax_t)gid);
521
552
case 132: /* --debug */
555
case 133: /* --plugin-helper-dir */
556
free(pluginhelperdir);
557
pluginhelperdir = strdup(arg);
558
if(pluginhelperdir != NULL){
525
563
* These reproduce what we would get without ARGP_NO_HELP
527
565
case '?': /* --help */
528
566
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
529
567
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
568
__builtin_unreachable();
530
569
case -3: /* --usage */
531
570
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
532
571
argp_state_help(state, state->out_stream,
533
572
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
573
__builtin_unreachable();
534
574
case 'V': /* --version */
535
575
fprintf(state->out_stream, "%s\n", argp_program_version);
536
576
exit(EXIT_SUCCESS);
783
864
ret = set_cloexec_flag(dir_fd);
785
866
error(0, errno, "set_cloexec_flag");
786
TEMP_FAILURE_RETRY(close(dir_fd));
787
867
exitstatus = EX_OSERR;
790
870
#endif /* O_CLOEXEC */
792
dir = fdopendir(dir_fd);
794
error(0, errno, "Could not open plugin dir");
795
TEMP_FAILURE_RETRY(close(dir_fd));
796
exitstatus = EX_OSERR;
873
int good_name(const struct dirent * const dirent){
874
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
875
"*.dpkg-old", "*.dpkg-bak",
876
"*.dpkg-divert", NULL };
878
#pragma GCC diagnostic push
879
#pragma GCC diagnostic ignored "-Wcast-qual"
881
for(const char **pat = (const char **)patterns;
882
*pat != NULL; pat++){
884
#pragma GCC diagnostic pop
886
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
889
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
890
" matching pattern %s\n", dirent->d_name, *pat);
898
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
900
if(numplugins == -1){
901
error(0, errno, "Could not scan plugin dir");
903
exitstatus = EX_OSERR;
801
907
FD_ZERO(&rfds_all);
803
909
/* Read and execute any executable in the plugin directory*/
806
dirst = readdir(dir);
807
} while(dirst == NULL and errno == EINTR);
809
/* All directory entries have been processed */
812
error(0, errno, "readdir");
813
exitstatus = EX_IOERR;
819
d_name_len = strlen(dirst->d_name);
821
/* Ignore dotfiles, backup files and other junk */
823
bool bad_name = false;
825
const char const *bad_prefixes[] = { ".", "#", NULL };
827
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
830
".dpkg-divert", NULL };
831
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
832
size_t pre_len = strlen(*pre);
833
if((d_name_len >= pre_len)
834
and strncmp((dirst->d_name), *pre, pre_len) == 0){
836
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
837
" with bad prefix %s\n", dirst->d_name, *pre);
846
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
847
size_t suf_len = strlen(*suf);
848
if((d_name_len >= suf_len)
849
and (strcmp((dirst->d_name) + d_name_len-suf_len, *suf)
852
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
853
" with bad suffix %s\n", dirst->d_name, *suf);
866
if(plugindir == NULL){
867
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
870
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
875
error(0, errno, "asprintf");
910
for(int i = 0; i < numplugins; i++){
912
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
914
error(0, errno, "Could not open plugin");
879
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
918
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
881
920
error(0, errno, "stat");
886
926
/* Ignore non-executable files */
887
927
if(not S_ISREG(st.st_mode)
888
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
928
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
890
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
891
" with bad type or mode\n", filename);
931
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
932
" with bad type or mode\n",
933
plugindir != NULL ? plugindir : PDIR,
934
direntries[i]->d_name);
897
plugin *p = getplugin(dirst->d_name);
941
plugin *p = getplugin(direntries[i]->d_name);
899
943
error(0, errno, "getplugin");
905
950
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
951
direntries[i]->d_name);
994
1067
_exit(EX_OSERR);
998
/* If dir has no file descriptor, we could not set FD_CLOEXEC
999
above and must now close it manually here. */
1002
if(p->environ[0] == NULL){
1003
if(execv(filename, p->argv) < 0){
1004
error(0, errno, "execv");
1008
if(execve(filename, p->argv, p->environ) < 0){
1009
error(0, errno, "execve");
1070
if(fexecve(plugin_fd, p->argv,
1071
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1072
error(0, errno, "fexecve for %s/%s",
1073
plugindir != NULL ? plugindir : PDIR,
1074
direntries[i]->d_name);
1013
1077
/* no return */
1015
1079
/* Parent process */
1016
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
1019
plugin *new_plugin = getplugin(dirst->d_name);
1080
close(pipefd[1]); /* Close unused write end of pipe */
1082
plugin *new_plugin = getplugin(direntries[i]->d_name);
1020
1083
if(new_plugin == NULL){
1021
1084
error(0, errno, "getplugin");
1022
1085
ret = (int)(TEMP_FAILURE_RETRY